The drying of mucous membranes is a common trouble in adult population, and the usual "cause" of drying is ageing. Every fourth or fifth adult suffers, for example, from dry mouth (Tenovuo, J. and Soderling, E., Suomen Hammaslaakarilehti 17 (1994) 972-979). A dry sensation in the mouth is more common in women than in men, which is largely due to hormonal changes: a postmenopausal drop in the oestrogen hormone concentration causes the mucous membranes of not only the vagina and female genitals but also of the mouth and eyes to dry.
The mucous membranes may also dry as a result of some external cause or situation: dry, windy weather; dry indoor air particularly in winter; a too high or too low room temperature; incorrect working position at a terminal; or watching of a TV set positioned too high may dry nasal and oral mucous membranes. Nervousness caused, for example, by a public performance; continuous speaking, for example, at a lecture; and a state of stress in which adrenalin production rises also dry the mouth.
In addition, symptoms caused by the drying of mucous membranes are also associated with many diseases and drugs used in their treatment. Dry mouth is particularly common in connection with the use of psychopharmaceuticals, and drugs used for the treatment of cardiac diseases, asthma and high blood pressure. In some rheumatic conditions and in connection with radiotherapy on the neck and nape, both mouth and eyes may dry. Further, for example, anti-allergy and anti-histamine medication dry nasal mucous membranes, particularly if nasal sprays are used frequently.
The drying of mucous membranes appears as a tight sensation, smarting, itching, pain, irritation, an uncomfortable sensation, problems in speaking, swallowing or chewing, a need to drink or to blink or moisten the eyes, to wash, etc. In addition, wounds, or apthae, appear easily on dry mucous membranes, whereby the mucous membranes easily bleed and become inflamed. A reduced amount or complete lack of saliva particularly in a dry mouth increases dental caries and, irrespective of the cause of dry mouth, oral hygiene is of primary importance if the oral mucous membranes are dry.
There are different commercially available products to alleviate the symptoms of dry mucous membranes: xylitol chewing gums and lozenges alleviating the symptoms of dry mouth and stimulating salivation; artificial saliva preparations moistening mucous membranes; eye drops and gels and nasal sprays and mist sprays alleviating the symptoms of dry eyes and nose, respectively; hormonal creams and vaginal suppositories, preparations containing lactic acid bacteria, moistening vaginal suppositories, and other such products used for alleviating the symptoms caused by drying of the vaginal mucous membranes. However, still new products are needed to alleviate and eliminate, preferably for a longer period of time and possibly on a prophylactic basis, the symptoms of dry mucous membranes, simultaneously avoiding the side effects of the currently available products.
An object of the present invention is to provide preparations that alleviate the symptoms caused by the drying of the mucous membranes of the body. Another object of the present invention is to provide a method of alleviating the symptoms, caused by drying, appearing on the mucous membranes of the mouth, eyes, nose or genitals.